MAGNETOMETRIC DEVICE FOR INTRUDER ALARM Russian patent published in 2006 - IPC G08B13/24 

FIELD: engineering of protective alarms, in particular, magnetometric devices for detecting intruders and their movement direction, based on passive method of registration of changes of magnetic field, caused by their intersection with protected boundary.

SUBSTANCE: device has unified cable three-lined magnetometric sensitive element, forming two lying near each other inductive differential signaling indicators and inductive interference indicator, enveloping both signaling indicators by area, signals from which are amplified, filtered and processed in device, so that it is possible, in accordance to discerning marks, to remove interference and separate useful signals, caused by intruder, in accordance to which device produces output signals.

EFFECT: substantially reduced number of false alarms of device, expanded area of possible use.

6 cl, 12 dwg